A stack manufacturing apparatus which progressively feeds a hooped long material to be machined in its longitudinal direction, forms relief holes within the outer contour of a stack or protrusions in positions corresponding to the relief holes at a plurality of stages, shapes component members having a predetermined outer contour by non-separating indentation machining into a state where at least part of the outer contour thereof is locked to the material to be machined, and successively presses out and stacks the component members, passes the projections through the relief holes in the lower component member(s), and welds the protrusions to another component member in a non-adjacent state for stack and integration in the final stage of the progressive feeding of the material to be machined has conventionally been disclosed (see Patent Literature 1).